This species is distinguished by the following characters: body deep, its depth 2.2-2.7 times in standard length; dorsal profile of head straight to above eye, then becoming convex; adults develop a large hump on forehead that can protrude anterior to eye; anterior tip of head forming an acute angle; jaws and lips prominent, 2 strong canines anteriorly in each jaw; no enlarged tooth present of rear of upper jaw; D IX,10, continuous; A III,8; dorsal and anal fins of adults very pointed, reaching well posterior to caudal-fin base; pelvic fins of small fish reaching anus, extending beyond anal-fin origin in large adults; pectoral fins with ii unbranched and 10 branched rays; caudal fin rounded; lateral line interrupted below posterior portion of dorsal-fin base, with a total of 22-23 pored scales; scales reaching well onto bases of dorsal and anal fins; scales in front of dorsal fin extending forward to above centre of eye; cheek and opercle scaly; lower jaw without scales. Colour of body olive to green with a vertical dark bar on each scale above and behind pectoral fins; head of adults blue-green to blue with highly irregular undulating yellowish lines; 2 black lines extending posteriorly from eye. Juvenile coloration lighter to white with dark scale bars and prominent black lines extending posteriorly from eyes, as well as 2 lines extending diagonally up and back from eye and 2 diagonally downward on snout in front of eye (Ref. 9823).